Jump to content

Rear Disc Direction In Trials Use


Greetings

Recommended Posts

well, I'm making a disc coversion for my mod frame, and was wondering if the disc shouldnt be mounted the other way round. damn my english is no good to explain my point so here's a drawing:

IPB Image

the point is that in trials, you stop the wheel from going backwards, not fowards. it's as if you were mounting a disc the other way round when riding normally (ie. downhill). that's not good because it causes the disc to collapse. apart from that, forces on brakes in trials are much larger than in any other bike sports i think. opinion?

Edited by Inur
Link to comment
Share on other sites

I never heard of anyone cracking a disc...

I've heard of several! Bigman cracked his Hope Trial rotor in 5 places!

Thing to remember in trials is that the forces go forwards as well as backwards, such as when you come up short in a gap (backwards) or just stop normally, so it doesn't matter which way you put it.

(Y)

Link to comment
Share on other sites

I've heard of several! Bigman cracked his Hope Trial rotor in 5 places!

Thing to remember in trials is that the forces go forwards as well as backwards, such as when you come up short in a gap (backwards) or just stop normally, so it doesn't matter which way you put it.

(Y)

i think hes cracked 3 of them now mike!

Link to comment
Share on other sites

Turning it round makes the difference between the forces pulling along the spokes of the disc, or pushing along them.

In reality i don't think it makes any difference which way round the disc is. I'm open to suggestions though if anyones got any good theories.

Link to comment
Share on other sites

Perhaps it's because he's a 'big man' and puts more force on a brake than your average 10-11 stone rider?

Its six of one, half a dozen of the other, if its going to break, it'll break regardless of which way you put it because as pointed out, the forces are not all acting in the one direction as is the case with xc bikes or downhill.

Link to comment
Share on other sites

Plenty of people put their discs on the "wrong" way around, it doesn't really make any difference. I never heard of anyone cracking a disc...

yup seconded! I ran both my mini disc brakes on my jump bike for a year or so on the wrong way round..... never noticed a difference to when i put them on properly!!

Link to comment
Share on other sites

yup seconded! I ran both my mini disc brakes on my jump bike for a year or so on the wrong way round..... never noticed a difference to when i put them on properly!!

just OT: did you find the brakes strong enough? were they the trials or just mini? thinking of getting some myself.

Link to comment
Share on other sites

just OT: did you find the brakes strong enough? were they the trials or just mini? thinking of getting some myself.

I used to run a Hope Mini 165mm on the bakc of my trials bike (now on my jump bike) and i progressed so much when i changed from a Mini to a Magura.

Unless you were getting a Mono Trials, I'd stick with Magura/V brakes.

Link to comment
Share on other sites

Turning it round makes the difference between the forces pulling along the spokes of the disc, or pushing along them.

I dont get what you mean... surely, as the brake surface is the same on either side, the rotor will stop with the same force because of the pads...which stops the wheel. so why would it differ if you turn it round?

Link to comment
Share on other sites

If the argument is about which way round, or forces on the disc, then although it would be heavy, why not make an actual full disc, a completely solid circular sheet of metal. That way there would be no weak points, and no possible breakages. BOOO YIP!!!!

Ps: Im not sober by a long shot

Link to comment
Share on other sites

All running my tyres round the wrong way was to pull off all the little nobbly bits!

On a disk i dont see what difference it would make on some tyres it says like ----> performane <----- durobulity ??sp?? i trust Hope (or the disk manafacturer) if they would have wanted to let you now a disk gives more power the wrong way round then they wouuld have told you. id say it doesnt make any difference myself

Link to comment
Share on other sites

i trust Hope (or the disk manafacturer) if they would have wanted to let you now a disk gives more power the wrong way round then they wouuld have told you. id say it doesnt make any difference myself

they probably would, but putting it the other way round doesn't give you more power, it's just more mechanically sound.

EDIT: don't want to start another topic, if the mini are too weak, would an M4 hope be good enough? 20" wheels, 8"/7" disc on the rear?

Edited by Inur
Link to comment
Share on other sites

dont forget discs have come from a XC background????? the wheels only ever go forward and dont really slip backwards as there not jumping up walls like us are they?

the theory is good and works BUT in trials if you turn the disc around you may find that it does work better (Y) the way to do it is to try it :D

Waynio............................

yes the Mono M4 would be way powerful enough with a 180mm rotor (Y) there really strong and powerful brakes compared to the standard mini, but if your spending that £££ why not buy a trials disc???

Edited by Waynio
Link to comment
Share on other sites

"why not make an actual full disc, a completely solid circular sheet of metal. That way there would be no weak points, and no possible breakages. BOOO YIP!!!!"

Wouldn't work because of the heat, the holes in the rim are mean to allow air to flow a bit ~(in theory)~ but they do look prety with holes to :) a soldi disk would be ugly and heavy(er)

Link to comment
Share on other sites

IMO a full disc could actually be weaker. its like a pipe being stronger than a rod. that's just a guess :)

Pipes are only stronger than a rod for a given weight though. A full disc isn't going to be weaker, but it probably won't be much stronger and it would be a lot heavier. Like I said, breaking discs is not an issue*.

*see above

Link to comment
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

Loading...
  • Recently Browsing   0 members

    • No registered users viewing this page.
×
×
  • Create New...